Automated recognition of the major muscle injury in athletes on X-ray CT images1

BACKGROUND

In this research, imaging techniques such as CT and X-ray are used to locate important muscles in the shoulders and legs. Athletes who participate in sports that require running, jumping, or throwing are more likely to get injuries such as sprains, strains, tendinitis, fractures, and dislocations. One proposed automated technique has the overarching goal of enhancing recognition.

OBJECTIVE

This study aims to determine how to recognize the major muscles in the shoulder and leg utilizing X-ray CT images as its primary diagnostic tool.

METHODS

Using a shape model, discovering landmarks, and generating a form model are the steps necessary to identify injuries in key shoulder and leg muscles. The method also involves identifying injuries in significant abdominal muscles. The use of adversarial deep learning, and more specifically Deep-Injury Region Identification, can improve the ability to identify damaged muscle in X-ray and CT images.

RESULTS

Applying the proposed diagnostic model to 150 sets of CT images, the study results show that Jaccard similarity coefficient (JSC) rate for the procedure is 0.724, the repeatability is 0.678, and the accuracy is 94.9% respectively.

CONCLUSION

The study results demonstrate feasibility of using adversarial deep learning and deep-injury region identification to automatically detect severe muscle injuries in the shoulder and leg, which can enhance the identification and diagnosis of injuries in athletes, especially for those who compete in sports that include running, jumping, and throwing.

Specific collagen peptides increase adaptions of patellar tendon morphology following 14-weeks of high-load resistance training: A randomized-controlled trial

ABSTRACTThe purpose of this study was to investigate the effect of a supplementation with specific collagen peptides (SCP) combined with resistance training (RT) on changes in structural properties of the patellar tendon. Furthermore, tendon stiffness as well as maximal voluntary knee extension strength and cross-sectional area (CSA) of the rectus femoris muscle were assessed. In a randomized, placebo-controlled study, 50 healthy, moderately active male participants completed a 14-week resistance training program with three weekly sessions (70-85% of 1 repetition maximum [1RM]) for the knee extensors. While the SCP group received 5g of specific collagen peptides daily, the other group received the same amount of a placebo (PLA) supplement. The SCP supplementation led to a significant greater (p < 0.05) increase in patellar tendon CSA compared with the PLA group at 60% and 70% of the patellar tendon length starting from the proximal insertion. Both groups increased tendon stiffness (p < 0.01), muscle CSA (p < 0.05) and muscular strength (p < 0.001) throughout the intervention without significant differences between the groups. The current study shows that in healthy, moderately active men, supplementation of SCP in combination with RT leads to greater increase in patellar tendon CSA than RT alone. Since underlying mechanisms of tendon hypertrophy are currently unknown, further studies should investigate potential mechanisms causing the increased morphology adaptions following SCP supplementation.Trial registration: German Clinical Trials Register identifier: DRKS00029244..

Magnetic Resonance Imaging Evaluation of Multifidus Muscle in Patients with Low Back Pain after Microlumbar Discectomy Surgery

Cross-sectional area (CSA) and signal intensity ratio (SIR) of the multifidus muscle (MFM) on magnetic resonance imaging (MRI) was used to evaluate the extent of injury and atrophy of the MFM in patients with negative treatment outcomes following microlumbar discectomy (MLD). Negative treatment outcome was determined by pain score improvement of <50% compared to baseline. Patients in groups 1, 2, and 3 were evaluated at <4 weeks, 4-24 weeks, and >24 weeks postoperatively, respectively. The associations between the follow-up, surgery time and the changes in the MFM were evaluated. A total of 79 patients were included, with 22, 27, and 30 subjects in groups 1, 2, and 3, respectively. The MFM SIR of the ipsilateral side had significantly decreased in groups 2 (p = 0.001) and 3 (p < 0.001). The ipsilateral MFM CSA significantly decreased postoperatively in groups 2 (p = 0.04) and 3 (p = 0.006). The postoperative MRI scans found significant MFM changes on the ipsilateral side in patients with negative treatment outcomes regarding pain intensity following MLD. As the interval to the postoperative MRI scan increased, the changes in CSA of the MFM and change in T2 SIR of the MFM showed a tendency to increase.

Morphological Changes of the Suboccipital Musculature in Women with Myofascial Temporomandibular Pain: A Case-Control Study

Temporomandibular disorder (TMD) is an umbrella term including pain problems involving the cranio-cervical region. It has been suggested that patients with TMD also exhibit cervical spine disturbances. Evidence suggests the presence of morphological changes in the deep cervical muscles in individuals with headaches. The objective of this study was to compare the morphology of the suboccipital muscles between women with TMD and healthy controls. An observational, cross-sectional case-control study was conducted. An ultrasound examination of the suboccipital musculature (rectus capitis posterior minor, rectus capitis posterior major, oblique capitis superior, oblique capitis inferior) was conducted in 20 women with myofascial TMD and 20 matched controls. The cross-sectional area (CSA), perimeter, depth, width, and length of each muscle were calculated by a blinded assessor. The results revealed that women with myofascial TMD pain exhibited bilaterally reduced thickness, CSA, and perimeter in all the suboccipital muscles when compared with healthy women. The width and depth of the suboccipital musculature were similar between women with myofascial TMD and pain-free controls. This study found morphological changes in the suboccipital muscles in women with myofascial TMD pain. These changes can be related to muscle atrophy and are similar to those previously found in women with headaches. Future studies are required to investigate the clinical relevance of these findings by determining if the specific treatment of these muscles could help clinically patients with myofascial TMD.

Does initial skeletal muscle size or sex affect the magnitude of muscle loss in response to 14 days immobilization?

We aimed to determine whether there was a relationship between pre-immobilization skeletal muscle size and the magnitude of muscle atrophy following 14 days of unilateral lower limb immobilization. Our findings (n = 30) show that pre-immobilization leg fat-free mass and quadriceps cross-sectional area (CSA) were unrelated to the magnitude of muscle atrophy. However, sex-based differences may be present, but confirmatory work is required. In women, pre-immobilization leg fat-free mass and CSA were associated with changes in quadriceps CSA after immobilization (n = 9, r² = 0.54-0.68; P < 0.05). The extent of muscle atrophy is not affected by initial muscle mass, but there is potential for sex-based differences.

[Evaluation of cross-sectional area and morphological value of external auditory meatus in concha plasty with I shaped incision]

Objective:To evaluate the preliminary value of the cross-sectional area and morphological changes of the external ear canal opening after the two-flap auriculoplasty through the I shaped posterior incision. Methods:One hundred and thirty-seven patients（a total of 155 ears） who received open radical mastoidectomy in the department of otolaryngology in the First Affiliated Hospital of Kunming Medical University were treated with I shaped incision and two-flap auriculoplasty. Vertical diameter（D1） and horizontal diameter（D2） of the external ear canal were measured at the completion of surgery, 1 month and 6 months post-operation, respectively. The cross-sectional area（S=1/4πD1×D2） of the external ear canal was calculated according to the two diameters. The dry ear time and intraoperative lumen epithelialization time were observed after operation. At 6 months after operation, the morphology of the external ear canal opening was analyzed. Results:The postoperative dry ear duration was 18-61 days（27.32±7.52） days. The time to complete epithelialization of the operative cavity was 24-70 days（32.18±10.36） days. Six months after the operation, the morphological classification of 155 outer ear meatal openings was as follows: 117 ears（ 75.48%） were round（the difference between vertical diameter and horizontal diameter was within 2 mm）; Oval（oval appearance, difference between vertical diameter and horizontal diameter greater than 2 mm） 35 ears（22.58%）, triangle 3 ears（1.94%）; Irregular ear canal orifice was not observed in all cases. During the operation, and at 1 month and 6 months after the operation, the cross-sectional area of the external ear canal was（2.51±0.48） cm², （2.45±0.35） cm², （2.41±0.43） cm², respectively. And no significant differences were observed. （P>0.05）. Conclusion:The I shaped posterior auricular incision and two-flap auricular lumenoplasty is not compex and easy to perform. The morphology of the external ear opening is regular after the operation, which can effectively match the ventilation of the operative cavity.

Diagnosis of carpal tunnel syndrome in non-diabetic patients with hemodialysis using ultrasound: Is it a useful adjunctive tool?

OBJECTIVE

(1) To examine the ultrasound (US) characteristics in patients with hemodialysis-related carpal tunnel syndrome (H-CTS) and (2) to evaluate the accuracy of a proposed US parameter-dynamic ratio of median nerve-to-hamate hook distance (RMHD) in diagnosis of H-CTS.

DESIGN

A case-control study.

SETTING

In a tertiary medical center and a secondary hospital from Nov. 2017 to Mar. 2021.

PARTICIPANTS

Consecutive non-diabetes patients under hemodialysis were recruited and divided into a hemodialysis without CTS (H-Control) group and an H-CTS group. Age-matched volunteers without diabetes or upper extremity disorders were enrolled as the Control group.

INTERVENTION

Ultrasound examinations by two operators blinded to the patient's clinical information.

MAIN OUTCOME MEASURES

US parameters including cross-sectional area of the median nerve at the carpal tunnel inlet (CSA-I) and outlet (CSA-O), the flattening ratio of the median nerve at the inlet (FR-I) and outlet (FR-O), and RMHD.

RESULTS

Handedness and arteriovenous fistula showed no associations with CSA-I/O and FR-I/O. Compared with Control group (n=69), the CSA-I was significantly larger in the H-Control group (n=63) and H-CTS group (n=76) (p<0.05). There were no significant differences in the FR-I/-O among the three groups. For the second aim, in the H-CTS group(n=38), there was a significantly lower RMHD compared with both the Control (n=20) and H-Control groups (n=30) (0.1%±2.2% versus 3.5±2.3% and 3.8±1.7%, p<0.05). An RMHD cutoff value of <2.7% yielded a specificity of 80.0%, a sensitivity of 94.7%, and an overall accuracy of 88.2% in the diagnosis of H-CTS.

CONCLUSIONS

Neither CSA-I/-O or FR-I/-O have a role in the diagnosis of H-CTS. RMHD might be a useful US parameter in the diagnosis of CTS in non-diabetic patients undergoing hemodialysis.

Sonographic Follow-Up of Patients With Cubital Tunnel Syndrome Undergoing in Situ Open Neurolysis or Endoscopic Release: The SPECTRE Study

Background:The measurement of cross-sectional area (CSA) is a diagnostic tool to detect entrapments syndrome. The aim of this study was to compare the clinical outcome in elbows undergoing endoscopic and "in situ" open cubital tunnel release for cubital tunnel syndrome (CuTS) using ultrasound-related changes in the largest CSA of the ulnar nerve. The purpose is to determine the association between clinical outcome and CSA. Methods: From May 2011 to April 2016, 60 patients with CuTS were prospectively followed and not randomly divided in two groups: 30 patients undergoing an endoscopic release (ER) and 30 patients with "in situ" open neurolysis (OR). A sonographic examination was performed by the senior authors at baseline and 3, 6, and 12 months after surgical decompression. Results: CSA values were statistically significantly lower in the ER. Hand grip strength difference with Jamar test was not statistically significant a 12 months (39 kg vs 27 kg). Static-2 point discrimination test difference was only statistically significant lower in the endoscopic group at 3, 6 and 12 months but not clinically relevant (5 mm vs 6 mm). The American Shoulder and Elbow Surgeons-Elbow questionnaire (ASES-e) function score, ASES-e Pain score, and ASES-e Satisfaction score were not statistically significant different between the two groups at 3, 6, and 12 months post operatively. Conclusions: The study confirms that in spite of lower values of CSA in the ER, there is not a statistically significant difference between the two techniques in terms of subjective outcomes. Ultrasound (US) measurements seem to have a limited value in clinical results of patients treated for entrapment neuropathy of the ulnar nerve.Type of study/LOE: Prognostic Level III.

Association of Lumbar Paraspinal Muscle Morphometry with Degenerative Spondylolisthesis

The objective of this study was to assess the cross-sectional areas (CSA) of lumbar paraspinal muscles and their fatty degeneration in adults with degenerative lumbar spondylolisthesis (DLS) diagnosed with chronic radiculopathy, compare them with those of the same age- and sex-related groups with radiculopathy, and evaluate their correlations and the changes observed on magnetic resonance imaging (MRI). This retrospective study included 62 female patients aged 65–85 years, who were diagnosed with lumbar polyradiculopathy. The patients were divided into two groups: 30 patients with spondylolisthesis and 32 patients without spondylolisthesis. We calculated the CSA and fatty degeneration of the erector spinae (ES) and multifidus (MF) on axial T2-weighted magnetic resonance (MR) images from the inferior end plate of the L4 vertebral body levels. The functional CSA (FCSA): CSA ratio, skeletal muscle index (SMI), and MF CSA: ES CSA ratio were calculated and compared between the two groups using an independent t-test. We performed logistic regression analysis using spondylolisthesis as the dependent variable and SMI, FCSA, rFCSA, fat infiltration rate as independent variables. The result showed more fat infiltration of MF in patients with DLS (56.33 vs. 44.66%; p = 0.001). The mean FCSA (783.33 vs. 666.22 mm²; p = 0.028) of ES muscle was a statistically larger in the patients with DLS. The ES FCSA / total CSA was an independent predictor of lumbar spondylolisthesis (odd ratio =1.092, p = 0.016), while the MF FCSA / total CSA was an independent protective factor (odd ratio =0.898, p = 0.002)

Isokinetic training - its radiographic and inflammatory effects on chronic low back pain: A randomized controlled trial

BACKGROUND

Isokinetic training (IKT) and core stabilization training (CST) are commonly used for balance training in musculoskeletal conditions. The knowledge about the effective implementation of these training protocols on radiological and biochemical effects in university football players with chronic low back pain (LBP) is lacking.

OBJECTIVE

To find and compare the effects of isokinetic training and CST on radiological and biochemical effects in university football players with chronic LBP.

DESIGN

Randomized, double-blinded controlled study.

SETTING

University hospital.

PARTICIPANTS

60 LBP participants were randomized into isokinetic group (IKT; n = 20), core stabilization group (CST; n = 20) and the control group (n = 20) and received respective exercises for 4 weeks.

OUTCOME MEASURES

Radiological (muscle cross sectional area & muscle thickness) and biochemical (C-reactive protein, tumor necrosis factor -α, interleukin [IL]-2, IL-4, IL-6) values were measured at baseline and after 4 weeks (immediate effect).

RESULTS

The reports of the IKT, CST and control group were compared between the groups. Four weeks following training IKT group shows more significant changes in muscle cross sectional area (Psoas Major, Quadratus Lumborum, Multifidus and Erector Spinae muscles) and muscle thickness (Multifidus) than CST and control groups (p < 0.001). Biochemical measures such as C-reactive protein, tumor necrosis factor -α, IL-2, IL-4 and IL-6 also show significant improvement in IKT group than the other 2 groups (P < .001).

CONCLUSION

Training through Isokinetic is an effective treatment program than conventional exercise programs in the aspect of radiological and biochemical analysis in university football players with chronic LBP, which may also help to prevent further injury. The present study can be used to improve the physical therapist's knowledge and clinical decision skills on LBP in football players.

Muscle function and size in the lumbar spine before and after a four week exercise intervention

BACKGROUND

Exercise of the spinal muscles is recommended for a variety of rehabilitative reasons but it is not always clear whether interventions are effective in improving the performance of the muscles or whether their benefit is elicited via other mechanisms.

OBJECTIVE

To explore the effects of an exercise intervention on the size and exercise performance of the lumbar spine extensor muscles.

METHODS

Eleven healthy participants undertook a four week programme of exercise. Magnetic resonance imaging and phosphorus spectroscopy were performed before and after the intervention to determine the time to fatigue and phosphocreatine (PCr) depletion during a muscle endurance test (modified Biering-Sørensen) together with muscle cross-sectional area (CSA).

RESULTS

The post intervention measures were significantly different to the pre-intervention results for the time to fatigue (post-pre: 20.5 ± 22.7 s (P= 0.014)) and PCr depletion both at the point of fatigue (post-pre: 9.5 ± 11.9% (P= 0.024)) and at a matched time-point (post-pre: 12.2 ± 11.9% (P= 0.007)). CSA was not significantly different in any muscle.

CONCLUSIONS

Exercise improved the performance of the trunk muscles despite no impact on CSA. This demonstrated the importance of obtaining a wide range of measures when assessing the effectiveness of exercise intervention programmes.

Contribution of Lumbar Spine Pathology and Age to Paraspinal Muscle Size and Fatty Infiltration

STUDY DESIGN

Retrospective chart analysis of 199 individuals aged 18 to 80 years scheduled for lumbar spine surgery.

OBJECTIVE

The purpose of this study was to quantify changes in muscle cross-sectional area (CSA) and fat signal fraction (FSF) with age in men and women with lumbar spine pathology and compare them to published normative data.

SUMMARY OF BACKGROUND DATA

Pathological changes in lumbar paraspinal muscle are often confounded by age-related decline in muscle size (CSA) and quality (fatty infiltration). Individuals with pathology have been shown to have decreased CSA and fatty infiltration of both the multifidus and erector spinae muscles, but the magnitude of these changes in the context of normal aging is unknown.

METHODS

Individuals aged 18 to 80 years who were scheduled for lumbar surgery for diagnoses associated with lumbar spine pain or pathology were included. Muscle CSA and FSF of the multifidus and erector spinae were measured from preoperative T2-weighted magnetic resonance images at the L4 level. Univariate and multiple linear regression analyses were performed for each outcome using age and sex as predictor variables. Statistical comparisons of univariate regression parameters (slope and intercept) to published normative data were also performed.

RESULTS

There was no change in CSA with age in either sex (P > 0.05), but women had lower CSAs than men in both muscles (P < 0.0001). There was an increase in FSF with age in erector spinae and multifidus muscles in both sexes (P < 0.0001). Multifidus FSF values were higher in women with lumbar spine pathology than published values for healthy controls (P = 0.03), and slopes tended to be steeper with pathology for both muscles in women (P < 0.08) but not in men (P > 0.31).

CONCLUSION

Lumbar muscle fat content, but not CSA, changes with age in individuals with pathology. In women, this increase is more profound than age-related increases in healthy individuals.

LEVEL OF EVIDENCE

3.

Eccentric Ergometer Training Promotes Locomotor Muscle Strength but Not Mitochondrial Adaptation in Patients with Severe Chronic Obstructive Pulmonary Disease

Eccentric ergometer training (EET) is increasingly being proposed as a therapeutic strategy to improve skeletal muscle strength in various cardiorespiratory diseases, due to the principle that lengthening muscle actions lead to high force-generating capacity at low cardiopulmonary load. One clinical population that may particularly benefit from this strategy is chronic obstructive pulmonary disease (COPD), as ventilatory constraints and locomotor muscle dysfunction often limit efficacy of conventional exercise rehabilitation in patients with severe disease. While the feasibility of EET for COPD has been established, the nature and extent of adaptation within COPD muscle is unknown. The aim of this study was therefore to characterize the locomotor muscle adaptations to EET in patients with severe COPD, and compare them with adaptations gained through conventional concentric ergometer training (CET). Male patients were randomized to either EET (n = 8) or CET (n = 7) for 10 weeks and matched for heart rate intensity. EET patients trained on average at a workload that was three times that of CET, at a lower perception of leg fatigue and dyspnea. EET led to increases in isometric peak strength and relative thigh mass (p < 0.01) whereas CET had no such effect. However, EET did not result in fiber hypertrophy, as morphometric analysis of muscle biopsies showed no increase in mean fiber cross-sectional area (p = 0.82), with variability in the direction and magnitude of fiber-type responses (20% increase in Type 1, p = 0.18; 4% decrease in Type 2a, p = 0.37) compared to CET (26% increase in Type 1, p = 0.04; 15% increase in Type 2a, p = 0.09). EET had no impact on mitochondrial adaptation, as revealed by lack of change in markers of mitochondrial biogenesis, content and respiration, which contrasted to improvements (p < 0.05) within CET muscle. While future study is needed to more definitively determine the effects of EET on fiber hypertrophy and associated underlying molecular signaling pathways in COPD locomotor muscle, our findings promote the implementation of this strategy to improve muscle strength. Furthermore, contrasting mitochondrial adaptations suggest evaluation of a sequential paradigm of eccentric followed by concentric cycling as a means of augmenting the training response and attenuating skeletal muscle dysfunction in patients with advanced COPD.

Clinical importance of cross-sectional area of intercostal muscles in patients with chronic obstructive pulmonary disease

INTRODUCTION

Limb muscle wasting is one of main systemic manifestation of chronic obstructive pulmonary disease (COPD). However, the change of respiratory muscle is unclear.

OBJECTIVES

This study assessed the cross-sectional area (CSA) of the intercostal muscles (ICMs) in patients with COPD, using chest computed tomography (CT) and determined its association with the clinical characteristics of COPD.

METHODS

They retrospectively reviewed 60 patients with stable COPD and compared them with 30 controls. CSA (mm² ) of the ICM on chest CT was measured at the midline level of the lateral arch of the bilateral first rib with a 3-mm slice thickness by using CT histogram software. The association with the clinical characteristics of COPD and with the control groups was assessed.

RESULTS

CSA of the ICM and the CSA/body mass index (BMI) were lower in the COPD group than in the control group. Patients with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 4 had a significantly lower CSA of the ICM than patients with stage 1, 2, and 3. CSA of the ICM was positively associated with FEV₁ , %FEV₁ predicted, FEV₁ /FVC ratio, and BMI and negatively associated with age. However, there were no associations with PaO₂ , PaCO₂ , smoking status, 6-minute walk test, frequency of acute exacerbation of COPD, and serum C-reactive protein level.

CONCLUSION

Intercostal muscle atrophy occurs in COPD patients and is associated with severity of airway obstruction, BMI, and increasing age.

Quadriceps function relates to muscle size following ACL reconstruction

It remains unclear what role reduced volume and cross-section area (CSA) of individual quadriceps muscles may play in persistent quadriceps weakness and more global dysfunction following ACL reconstruction (ACLR). The purpose of this investigation was to establish the relationship between cross-sectional area of the quadriceps muscle group and measures of knee related and quadriceps function following ACLR. Thirty participants with a history of primary, unilateral ACLR experiencing persistent quadriceps activation failure participated in this cohort study. Clinical factors including International Knee Documentation Committee (IKDC) score, normalized knee extension MVIC torque (Nm/kg) and quadriceps central activation ratio (CAR, %) were assessed in addition to CSA. Quadriceps CSA was measured via magnetic resonance imaging (MRI; Siemens Avanto 1.5T). Quadriceps CSA (cm(2) ) and quadriceps volume (cm(3) ) as well as individual muscle estimates were identified within a 10 cm mid-thigh capture area. Pearson's product-moment correlation coefficients (r) established relationships between CSA and all other variables. Stepwise linear regression established which CSA factors were able to successfully predict clinical factors. Knee extension MVIC torque was strongly correlated with Vastus Intermedius (VI; r =  0.857, p < 0.001) CSA as well as partial VI (r = 0.849, p < 0.001) and quadriceps (r = 0.830, p < 0.001) volume. Partial VI (r = 0.365, p = 0.047) volume was weakly correlated with IKDC score. Knee extension MVIC torque was strongly predicted using VI CSA alone (R(2)  = 0.725) or in combination with Vastus Medialis CSA (VM; R(2)  = 0.756). Statement of Clinical Significance: Atrophy of the VI and VM muscles negatively impacts knee extension strength following ACLR. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1656-1662, 2016.

The effect of different exercise programs on cervical flexor muscles dimensions in patients with chronic neck pain

OBJECTIVE

The effect of different exercise programs on cervical flexor muscles dimensions in patients with chronic neck pain is yet to be demonstrated. The purpose of this study was to assess the effect of two exercise programs; craniocervical flexion (CCF) and cervical flexion (CF), on flexor muscles dimensions in patients with chronic neck pain.

METHODS

Following ethical approval, 60 patients were randomly assigned into either a CCF group or a CF group. Patients in the CCF group were given CCF exercises and those in the CF group received CF exercises. All patients received interventions for a period of ten weeks. Pain intensity and functional disability were assessed using numerical pain rate scale and neck disability index, respectively. Dimensions of longus colli (LC) and sternoclidomastoid (SCM) muscles were measured using ultrasonography (US). All measurements were taken before and after interventions.

RESULTS

Following intervention, the CCF group demonstrated a significant increase in LC muscle dimensions including cross sectional area, width and thickness compared with the CF group. A statistically significant increase was found on SCM thickness in the CF group. Following intervention, SCM thickness measurement in the CCF group showed no significant changes. Statistically significant decrease on pain intensity and disability were also found in both groups.

CONCLUSION

Present findings demonstrated that craniocervical flexion program which specifically recruiting deep cervical flexor muscles increased LC muscle dimension significantly and CF program as an endurance training program increased SCM thickness.

A semi-automatic framework of measuring pulmonary arterial metrics at anatomic airway locations using CT imaging

Pulmonary vascular dysfunction has been implicated in smoking-related susceptibility to emphysema. With the growing interest in characterizing arterial morphology for early evaluation of the vascular role in pulmonary diseases, there is an increasing need for the standardization of a framework for arterial morphological assessment at airway segmental levels. In this paper, we present an effective and robust semi-automatic framework to segment pulmonary arteries at different anatomic airway branches and measure their cross-sectional area (CSA). The method starts with user-specified endpoints of a target arterial segment through a custom-built graphical user interface. It then automatically detect the centerline joining the endpoints, determines the local structure orientation and computes the CSA along the centerline after filtering out the adjacent pulmonary structures, such as veins or airway walls. Several new techniques are presented, including collision-impact based cost function for centerline detection, radial sample-line based CSA computation, and outlier analysis of radial distance to subtract adjacent neighboring structures in the CSA measurement. The method was applied to repeat-scan pulmonary multirow detector CT (MDCT) images from ten healthy subjects (age: 21-48 Yrs, mean: 28.5 Yrs; 7 female) at functional residual capacity (FRC). The reproducibility of computed arterial CSA from four airway segmental regions in middle and lower lobes was analyzed. The overall repeat-scan intra-class correlation (ICC) of the computed CSA from all four airway regions in ten subjects was 96% with maximum ICC found at LB10 and RB4 regions.

A comparison of the ultrasonographic median nerve cross-sectional area at the wrist and the wrist-to-forearm ratio in carpal tunnel syndrome

BACKGROUND

Electrophysiologic (EDX) study is the most valuable method in grading the severity of carpal tunnel syndrome (CTS), but it is invasive and painful. We evaluated the efficacy of ultrasound for this purpose.

MATERIALS AND METHODS

Eighty-one wrists of 52 consecutive patients with clinical evidences of CTS, confirmed and graded by EDX as mild, moderate, and severe, were examined by ultrasonography. Cross-sectional area (CSA) of the median nerve was measured at the distal wrist (CSA-D), and proximal forearm (CSA-P), and wrist-to-forearm ratio (WFR) was calculated for each hand.

RESULTS

The mean CSA-D was 0.12 cm(2) ± 0.03, 0.15 cm(2) ± 0.03 and 0.19 cm(2) ± 0.06 and the mean WFR was 2.77 ± 1.14, 3.07 ± 1.07 and 4.07 ± 1.61 in mild, moderate and severe groups respectively. WFR showed significant differences between the severe and none severe CTS groups (P < 0.001), but there was no significant difference between mild and moderate CTS groups (P < 0.381). CSA-D showed a significant difference between all groups (P < 0.0001). In the Receiver Operating Characteristic curve analysis, the optimal cut-off value of the CSA-D and WFR for detecting severe CTS were 0.15 (area under the curve 0.784, 95% confidence interval (CI): 0.662-0.898, P < 0.001, sensitivity of 68.2% and specificity of 70.9%) and 3 (area under the curve 0.714, 95% CI: 0.585-0.84, P = 0.001, sensitivity of 68.2% and specificity of 64.8%) respectively. All values were superior in CSA-D.

CONCLUSION

Ultrasonography, can be complementary but not conclusive to the classification of CTS severities. CSA-D and WFR both increased in proportion to CTS severity, but neither parameter exhibited excellent performance in grading the severities.

Glial cell line-derived neurotrophic factor (GDNF) expression and NMJ plasticity in skeletal muscle following endurance exercise

Glial cell line-derived neurotrophic factor (GDNF) supports and maintains the neuromuscular system during development and through adulthood by promoting neuroplasticity. The aim of this study was to determine if different modes of exercise can promote changes in GDNF expression and neuromuscular junction (NMJ) morphology in slow- and fast-twitch muscles. Rats were randomly assigned to a run training (run group), swim training (swim group), or sedentary control group. GDNF protein content was determined by enzyme-linked immunosorbant assay. GDNF protein content increased significantly in soleus (SOL) following both training protocols (P<0.05). Although not significant, an increase of 60% in the extensor digitorum longus (EDL) followed swim-training (NS; P<0.06). NMJ morphology was analyzed by measuring α-bungarotoxin labeled post-synaptic end plates. GDNF content and total end plate area were positively correlated. End plate area decreased in EDL of the run group and increased in SOL of the swim group. The results indicate that GDNF expression and NMJ morphological changes are activity dependent and that different changes may be observed by varying the exercise intensity in slow- and fast-twitch fibers.

Muscle wasting in cancer

Skeletal muscle loss appears to be the most significant clinical event in cancer cachexia and is associated with a poor outcome. With regard to such muscle loss, despite extensive study in a range of models, there is ongoing debate as to whether a reduction in protein synthesis, an increase in degradation or a combination of both is the more relevant. Each model differs in terms of key mediators and the pathways activated in skeletal muscle. Certain models do suggest that decreased synthesis accompanied by enhanced protein degradation via the ubiquitin proteasome pathway (UPP) is important. Murine models tend to involve rapid development of cachexia and may represent more acute muscle atrophy rather than the chronic wasting observed in humans. There is a paucity of human data both at a basic descriptive level and at a molecular/mechanism level. Progress in treating the human form of cancer cachexia can only move forwards through carefully designed large randomised controlled clinical trials of specific therapies with validated biomarkers of relevance to underlying mechanisms. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.